Telephone and cap therefor



upg 7 F. WALTER I 1,631,350

TELEPHONE AND CAP THEREFOR Filed Dec. 1 1925 4, a a y j INV E N TO R I Hank Wa/fer $4M HIS ATTORNEY Patented June 7,, 1927.

' FRANK watmnn or tosnnonnns, panam v TELEPHONE AND CAP "THEREFOR.

Application filed December '16; 1925, seriarno. 75,755, a

This invention relates to a telephone re energized in accordance with the received signals, and a diaphragm of magnetic inaterial arranged to be affected by the magnet. In order to form an ear piece, a cap is provided for the device, which cap is usually screwed on close vto the diaphragm, and is provided with an aperture through which the vibrations of the air, produced by operation of the diaphragm, can affect limited to applications to radio, but can genunderstood that this detailed description is the ear.

It 18 common for enthusiasts 1n rad10,and

' for those attempting to'secure signals from distant points, tokeep the headphones on the ears for long intervals at a time. Under suchcircumstances, due to the formation of a confined space between the ear and the diaphragm, moisture usually collects thereon;

this is obviously undesirable not only be-- cause it offends the sense of cleanliness, but' because it interferes with proper reception. It is thus one of the objects of my invention to overcome these disadvantages in a telee phone, and especiallyvby the'prov'ision ofa" cap for'the diaphragm whichis formed to prevent the accumulation of moisture. In this connection, my invention is not at all erally be applied to all types of telephones. My invention also assists materially in clarifying the sound produced by the receiver; and I have found it to be of'especial benefit in connection with radio reception in which considerable power is availablein the audio frequency circuit, as for example, in sets utilizing two or more audions. In such sets, the clarification is marked with my in vention, and thevolume of sound is yet suflicient for all purposes. It can be applied'to loud speakers as well as to ear phones.

My invention possesses many other advantages, and has other objects which may be made more easily apparent from a consideration of several embodiments of my invention. For this purpose I have shown afew forms in thedrawings accompanying and forming partof the present specification; I shall now proceed'to describe these forms in detail, which illustrate the general principles of my invention; but it is to bearp c eclail Y the r -f l -tak n iri lim t ng sen e, in t e' $9019 fm-y. nvent o i be gd fined by h Referring to the dra i s};

' Figure 1 is a sectional'view of aitelephone embodying my lnventlon;

Fig. 2 is a perspective View of-a telephone fitted with my invention;

Fig. 3 isa sectional view of phone; and o Fig. 1 is a bottom view thereof. In Fig. 1, I show acircularbody or shell 11 of'insulating material, forming the main 7 a modified N form of cap that can be used with ateleas to affect in a well-understood manner, the

diaphragm .13. This diaphragm rests :on

the top edge of-the shell 11,.which is usually provided with screw threads. .7 The magnets 12 being permanently magnetized, prevent-3 movement 'of the diaphragm" away edges of the-shell 11.1

shell 11," and that defines'a space 15 over diaphragm of from the considerable height. 1 V

Apertures 16 are provided in the sides to permit air to enter and leave the space 15, lndependently of the ear opening 17'. j The cap 14 can be conveniently made'from soft rubber, and of such dimensions. that it will telescope snugly, oventhe shell" 11. The threads 18Hare illustrated on shell 11, to I show that existing shells can be used, by

removing vthe usual threaded cap and replacing it by the cap 1 1 of the present invention.v I i The' use of earphonesisuch as shown in 1 Figs. 1 and 2 results in co'nsid-erablea'dvantages'. For long intervals, the head set hay 111g such phones is comfortable. No 111013 ture can collect on diaphragm 13, due to'the circulation of the air past it through apertures 16. 7 Furthermore, it is noted that the signals are clearer, much ofthedisturbing noise found in radio sets being absent. I

believe this results from the, provision of a large free space 15 between the diaphragm 13 and the ear. This space is defined thin walls of the cap.

by the While soft rubberis advantageous to use f for the cap 1 .450 as to provide a comfort 19 has a series of oval holes 20, as well as internal screw threads 21, whereby it can be screwed on in place in a position similar to that shown in Figs. 1 and 2. The same principle of operation however, is present,

in this form as in that first described. In each "form of cap, there are one or more radial openingswhich are intended to communicate with a space between the diaphragm and the cap. r

my hand.

I claim A cap for a radio telephone receiver of the diaphragm type, said cap having an opening adapted to conduct the sound waves produced by the receiver, said cap extending over the diaphragm, the cap and said diaphragm defining a large, free space 1minediately interposed between the said open ing and the surface of substantially the entire diaphragm, said cap having radial openings connecting said space directly with the external atmosphere.

T In testimony whereof I have hereunto set FRANK WALTER. 

